Apparatus for the electrolysis of solutions of metal salts



'2 SHEETSSHEE, I.

Patented May 24 19211..

J. K. LANGHARD. APPARATUS FOR THE ELECTROLYSIS 0F SOLUTIONS OF METALSALTS.

7 APPLICATION FILED FEB. 6. I920.

. J. K; LANGHARD. APPARATUS FOR THE ELECTROLYSIS 0F SOLUTIONS-0F METALSALTS APPLICATION FILED FEB. 6, I920.

Patented. May 24. 192R STATES JOHANN KonnAD LANGHARD, or rnnnarxss'ran,Nonwar, assrsnon 'roq RIKSSTAD ELEKTROKEMISKE FABRIKER A/S., orrnnnnrnssran, NORW'AY.

APPARATUS FOR THE ELECTROLYSIS 01? SOLUTIONS OF METAL SALTS.

incense.

Patented May 24L, 12921..

Application filed February 6, 1920. Serial No. 356,652.

To all whom it may concern.

Be it known that I, JOHANN KONRAD LANG- nano, a citizen of Switzerland,residing at l redrilrsstad, Norway, have invented certain new and usefulImprovements in Apparatus for the Electrolysis of Solutions of MetalSalts; and I do hereby declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same, referencebeing had to the accompanying drawings, and to letters or figures ofreference marked thereon, which form a part of this specification.

The present invention relates to electrolyzers in which a layer of aloose granular material is employed to separate the anode and cathodespace from one another. The hitherto known electrolytic cells of thistype have been connected with various drawbacks involving inconveniencesduring the operation. Thus when a soluble separating layer such as ametal salt has been employed it has not been possible to compensate forthe salt dissolved during the electrolysis in such a manner as to attaina uniform distribution of the salt over the supporting means.

This and also other drawbacks are avoided according to the presentinvention by arranging the supporting means for the granular material atsuch an angle of in clination. that the introduced granular material isdistributed over the surface of the supporting means in consequence ofits own gravity.

By so arranging the apparatus it is also attained that the salt which isdissolved during the operation of the apparatus can be successivelyreplaced by new quantities of salt introduced through a charging opening arranged along the upper edge of the partition.

The invention also comprises means toprevent gas evolved during theelectrolysis from escaping through the charging opening for granularm-aterial.-

An embodiment of the invention is illustrated in the accompanyingdrawing, in which Figure l is a sectional view of the aggregatecomprising three individual cells.

Fig. 2 is an end View partly in section on the line A-B, Fig. 1, thecover 14 being removed.

F 1g. 3 is a plan view of a.- single cell, the cover of the anodecompartment bein removed. D

In the following description it is presumed that the apparatus isemployed for the electrolysis of chlorid of sodium. The apparatuscomprises a plurality of cells each having a vertical end wall 1, a wall1 arranged atan angle to the latter, and constituting an inclinedbottom, and two side walls 1 connecting the end and bottom walls. Theanode chamber 2 and cathode chamber 3, of each cell is separated by thinasbestos cloth 5 supported on an iron wire-cloth frame a which forms theca t-hode. The cathode frame '4: rests upon'narrow offsets 18 formed onthe side-walls 1 of the cells (Figs. 2 and 3) and current is supplied tosaid cathode through the connection 9 (l 'ig. 2). The thin asbestoscloth 5 which rests upon the cathode frame l prevents the granularmaterial 19, employed, from falling through the cathode. A wedge 6 ofhydraulic cement, a glass plate or the like prevents the chlorin gasfrom escaping, the electrolyte itself forming a liquid seal at the lowerend. At the top the anode compartment is closed by a cover 7. The anodes8 are inserted through holes in the cover and into the anode chamber andare supported upon a small offset at the lower end. The cover is alsoprovided with outlet openings 11. for the chlorin gases and withopenings 17 for the introduction of salt solution. The hydrogen evolvedescapes at 10, while the ly from the cathode compartment is drawn offthrough the outlets l2 and 13.

By means of uniting a greater or less number of single cellselectrolyzer aggregates of a greater or less size can be built up. Bygiving to the cells the construction illustrated in the drawing theinclined bottom wall of one cell will form the inclined cover of theadjacent cell. In the illustrated example the individual cells areconnected to one another by means of screws through the flanges 15 a.cover 14c being screwed on to the terminal cell.

When the electrolyzer aggregate is built up and it is to be put inoperation it is charged first with the salt solution to be electrolyzed.Solid salt is a crystalline condition is then introduced through theopening 16. The salt rapidly descends and becomes distributed over theentire'surface. Thisdistribution of the salt may also be controlled inthe manner that the cathode surface is constructed with a greater orless inclination. The apparatus can also be mounted so, as to enable itsdegree of inclination of being controlled as desired within certainlimits. The salt which is dissolved during the electrolysis is thenreplaced by maintaining the charging opening filled.

Concentrated pure salt solution is introduced through the pipe 17 eithercontinuously or at intervals. When a pure salt is charged into the cellsthe formation of sludge will be practicallyexcluded.

Owing to the fact that solid salt is constantly present in the cell theadvantage is also attained, that the electrolyte is maintained in aconcentrated condition which as known has an important influence uponthe current output.

It may be mentioned as an example that in practical operation of a cellof the construction above described a lye containing between 12 and 14per cent. caustic soda has been produced with a satisfactory currentoutput.

I claim:

1. In an electrolytic cell, a layer of loose granulated materialseparating the anode and cathode chambers, and supporting means for saidmaterial arranged at such an angle of inclination that granular materialsupplied thereto is distributed by gravity over the lower parts thereof.

2. An apparatus for the electrolysis of solutions, comprising aplurality of cells each having a layer of loose granulated materialseparating the anode and cathode chambers,

inclined supporting means for said material, said cells having openingsfor the introduction of the granulated material onto the supportingmeans, and partitions adjacent-said openings extending below the levelof the electrolyte forming closed gas collecting chambers above saidseparating layer.

3. An apparatus for the electrolysis of solutions comprising a pluralityof cells each having an inclined wire-cloth between the anode andcathode chambers, an asbestos cloth placed over the wire cloth, and alayer of loose granulated material deposited on the asbestos cloth. 1

4. An apparatus for the electrolysis of solutions comprising a pluralityof cells each having an inclined wire-cloth, between the anode andcathode chambers, an asbestos cloth placed over the wire cloth, a layerof loose granulated material deposited on the asbestos'cloth, and aninclined anode mounted 1in each cell above the granulated mater1a 5. Anapparatus for the electrolysis of solutions, comprising a plurality ofcells each having a vertical end wall and an inclined bottom wall, saidcells being so arranged in relation to each otherthat the inclinedbottom wall of one cell constitutes a cover for the adjacent cell.

6. 'An apparatus for the electrolysis of solutions comprising aplurality of cells each having a vertical end wall, a bottom wallarranged at an angle to the latter, a cathode mounted in each cellparallel to the bottom wall, an anode mounted above the cathode, apartition at the top of the cell between the anodes and cathodes andarranged to form an opening above the cathode, said partition extendingbelow the level ofthe electrolyte and forming a closed gas collectingchamber above the anode. v

7. An apparatus for the electrolysis of solutions comprising a pluralityof cells each having a vertical end wall and an inclined bottom Wall,said cells being so arranged in relation to each other that the inclinedbottom wall of one cell constitutes a cover for the adjacent cell, awire frame mounted in each cell parallel to the bottom wall, and forminga cathode between the anode and cathode chambers, an asbestos cloth overthe wire frame, a layer of loose granulated material on the asbestoscloth, an anode mounted above the granulated material, a partitionbetween the anode and cathode and arranged to form an opening above thecathode, said partition extending below the level of the electrolyteforming a closed gas collecting chamber above the granulated material.

8. The method of electrolyzing solutions which consists in continuouslysupplying-a quantity of soluble substance during the electrolysissufiicient to compensate for said substance as it is dissolved.

9. The method of electrolyzing solutions, which comprises maintaining bygravity a layer of salt to be electrolyzed on an inclined surfaceadjacent the cathode, thereby forming a continuous layer of said saltseparating the anode and the cathode chambers.

In testimony that I claim the foregoing as my invention, 1 have signedmy name in presence of two subscribing witnesses.

J OHANN KONRAD LANGHARD.

Witnesses:

NATH. A. LnnnNscHoN, ROBERT H. FRAZIER.

